This invention is directed to a chucking system wherein a keyless chuck is tightened or loosened by spindle rotation.
The most common type of chuck on such machine tools as drills, presses or other drill drivers, uses a key for tightening the chuck and clamping the drill in place. This type of key-tightened chuck has several disadvantages such as being unsafe and seldom having the key where it is needed.
To leave the key in the chuck is a common error, and when the drill driver is turned on, the chuck key can fly off at dangerous velocity.
Losing the key is a very common problem, and when this occurs, a most unsatisfactory substitute is to try to tighten the chuck with pliers or a wrench.
One solution to the lost key problem is to attach the key to the electric cord of a tool, but it is often just out of reach when it is most needed, such as when the user is on a ladder and the key is at the far end of the cord.
A further factor is the time lost in handling the key, even when it is conveniently available. Picking up the key, inserting it and turning it is a time-consuming manual activity, even when the key is conveniently placed. Using a key occasions unnecessary time loss.